Tool holders of the corresponding type are used also at different types of contractor's machinery such as excavators, wheel loaders, movers of material and the like machine types. A complication at tool holders for cranes such as, e.g., lorry cranes is that the tools are pendulum suspended, the tool holder being provided with a hydraulic rotator. Such a one is required at timber grip, clamshell bucket, pallet forks and other similar tools.
At conventional tool holders for cranes, hydraulic lines are run to the tool holder for the hydraulic maneuver of the tool as well as for maneuver of the locking mechanism of the tool holder. Since the locking mechanism consists of one or more double-acting hydraulic cylinders, two hydraulic lines are normally run for the locking function. With two or more hydraulic lines for maneuver of the tool, it means that at least four hydraulic lines are run to the tool holder. This implies a relatively complicated, and thereby expensive arrangement. On one hand because the hydraulic lines have to be run up along the entire crane jib, which becomes additionally cumbersome in connection with lorry cranes having a plurality of crane jib projections. And on the other hand because the rotators that most cranes are equipped with, normally only has one pair of swivel fairleads. For maneuver of the locking mechanism, additionally two swivel fairleads are required. It means that the rotator has to be provided with four coil ducts in the swivel, which implies a complication and price increase.
Tool holders of the above-mentioned type are manufactured by OilQuick AB at a system called OQ 60 and by Liebherr at a system called Topas.
Furthermore, a tool holder is previously known manufactured by HEVO Parts AB, at which the hydraulic hose problems are handled in a different way. In that connection, a hydraulic cylinder is integrated in the tool holder, which also serves as tool cylinder. By utilizing the existing work hydraulics under the rotator in this way, no connection of hoses at operation with, e.g., clamshell bucket and pallet forks is needed. At all other types of hydraulic tools, such as earth drill, vibrating tamper, etc., the hydraulic hoses, however, have to be connected as usual by hand. To interconnect hydraulic hoses by hand frequently involves problems, because of back-pressure in the lines as well as general oil mess. A disadvantage of said holder is that only specially adapted tools can be used in connection with the holder. Also size and weight of the holder are experienced as a disadvantage. The holder has mechanical locking, which is made by the operator by hand on site. By this holder, the hydraulic hose problems are partly solved.
The object of the present invention is to provide a tool holder of the kind in question, at which the disadvantages that are associated with previously known tool holders of the corresponding type are eliminated.